diff --git a/src/util-set-list.scm b/src/util-set-list.scm
index 998f568..076d041 100644
--- a/src/util-set-list.scm
+++ b/src/util-set-list.scm
@@ -223,6 +223,18 @@
 		   (list->lset '(1 2 3 1 2))
 		   (list->lset '(2 3 4 2 3))))
 		 4)
+    (test-equal? lset-intersect
+		 (lset-count
+		  (lset-intersect
+		   (list->lset '(1 2 3 1 2))
+		   (list->lset '(2 3 4 2 3))))
+		 2)
+    (test-equal? lset-subtract
+		 (lset-count
+		  (lset-subtract
+		   (list->lset '(1 2 3 1 2))
+		   (list->lset '(2 3 4 2 3))))
+		 1)
     ))
 
  )